1. Technical Field of the Invention
The invention is in the field of air vehicle control systems and methods.
2. Description of the Related Art
For present four-fin missiles steered by positioning the fins, a control actuation system (CAS) usually consists of four identical actuators, each with an identical independent controller tracking actuator commands. The CAS system includes a feedback mechanism that attempts to drive to zero any errors in the positions of the fins (differences between present fin positions and fin positions corresponding to roll, pitch, and yaw values commanded by an autopilot).
One way of dealing with possible faults in such a system is by detecting faults on individual CAS actuators, and then compensating in some way for any detected faults. This may be achieved by actively reconfiguring a mixing matrix (used for mapping autopilot commands to actuator commands) to transfer authority from a failed actuator to a redundant actuator. These methods require fault detection and active compensation, which increases complexity of a system, and may be inadequate for compensating for a large range of fault conditions.